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Robust passive control for uncertain nonlinear neutral Markovian jump systems with mode-dependent time-delays

ICIC Express Letters 2011年第1期5卷 119-126页

作者： Qiu, Jiqing Lu, Kunfeng Mahmoud, Magdi S. Yao, Na Du, Xiaoming College of Science Hebei University of Science and Technology No. 70 Yuhua East Rd. Shijiazhuang 050018 China Department of Automatic Control Beijing Institute of Technology No. 5 South Zhongguancun Street Haidian District Beijing 100081 China Systems Engineering Department KFUPM P. O. Box 985 Dhahran 31261 Saudi Arabia Science of College Chang'An University Mid-section of South Second Ring Road Xi'an 710064 China

This paper is concerned with the problem of robust passive control for uncertain nonlinear neutral system with mode-dependent time delays and Markovian jump parameters. First, novel robust stability criterion is investigated by utilizing the Lya- punov functional and combining with linear matrix inequality (LMI) approach. Then, a state feedback controller with Markovian jump parameters is established to guarantee that the resulting closed-loop system is robustly stable with an passive performance level. The time-varying delay function in this paper is not required to be either continuously differentiable, or its derivative less than one and dependent on the mode of operation. Finally, a numerical example is provided to illustrate the effectiveness of the proposed approach. © 2011 ISSN.

关键词： Linear matrix inequalities

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Modeling and experimental analysis of a 6-high industrial rolling mill vibration response

Modeling and experimental analysis of a 6-high industrial ro...

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7th International Conference on Condition Monitoring and Machinery Failure Prevention Technologies 2010, CM 2010/MFPT 2010

作者： Gryllias, Konstantinos C. Antoniadis, Ioannis A. National Technical University of Athens School of Mechanical Engineering Machine Design and Control Systems Section Dynamics and Structures Laboratory Athens 15773 Greece

ISBN: (纸本)9781618390134

During cold rolling of thin sheet, the operation is often accompanied by a variety of undesirable mechanical vibrations, generally referred to as chatter. Chatter is often associated with high rolling speeds and high thickness reductions, conditions that are generally desirable in order to increase mill productivity. Chatter can lead to unacceptable gauge fluctuations, sheet corrugations, surface imperfections, damage to mills and undesirable noise in the work environment. Four and six degree of freedom (DOF) systems describing chatter in sheet rolling in a 6-High rolling mill are proposed. The natural frequencies and the modes of the systems are extracted. The investigation includes the additional plastic deformation of the sheet in the roll-bite that is present during chatter as well as the force displacement relation between the cylindrical rolls being pressed together which is inherently nonlinear due to the changing contact area. It appears that the models are capable of predicting third octave chatter, in addition to fifth octave chatter. A number of mill operational parameters are considered. The models are validated using measurements performed at an industrial 6-high aluminium rolling mill.

关键词： Cold rolling

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A robust stabilization using state feedback with feedforward

A robust stabilization using state feedback with feedforward

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作者： Danapalasingam, Kumeresan A. La Cour-Harbo, Anders Chowdhary, Girish Bisgaard, Morten Department of Electronic Systems Section for Automation and Control Aalborg University 9220 Aalborg Denmark Georgia Institute of Technology Daniel Guggenheim School of Aerospace Engineering Atlanta GA United States

ISBN: (纸本)9781424474264

In a general nonlinear control system a stabilizing control strategy is often possible if complete information on external inputs affecting the system is available. Assuming that measurements of persistent disturbances are available it is shown that the existence of a smooth uniform control Lyapunov function implies the existence of a stabilizing state feedback with feedforward control which is robust with respect to measurement errors and external disturbances. Conversely, using differential inclusions parameterized as nonlinear systems with state and disturbance measurement errors, it is shown that there exists a smooth uniform control Lyapunov function if there is a robustly stabilizing state feedback with feedforward. This paper demonstrates that if there exists a smooth control Lyapunov function for a general nonlinear system with persistent disturbances for which one has previously designed a feedback controller, a feedforward always exists to be augmented for stability. © 2010 AACC.

关键词： Lyapunov functions

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A Device that can Produce Net Impulse Using Rotating Masses

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engineering（科研） 2010年第8期2卷 648-657页

作者： Christopher G. Provatidis Laboratory of Dynamics & Structures Mechanical Design & Control Systems Section School of Mechanical Engineering National Technical University of Athens

This paper describes a device capable of producing net impulse, through two synchronized masses, which move along a figure-eight-shaped orbit. In addition to the detailed description of the mechanical components of this device, particular attention is paid to the theoretical treatment of the innovative principle on which the device is based. In more details, the mechanical system consists of two independent but simultaneous rotations, the former being related to the formation of the figure-eight-shaped path and the latter to an additional spinning. Based on the parametric equations of motion of the lumped masses, and considering semi-static tensile deformation of the connecting rods carrying them, it was found that the resultant impulse towards the direction of the spin vector includes a non-vanishing term that is linearly proportional to the time. In addition, reduced but encouraging experimental results are reported. These findings sustain the capability of the proposed mechanism to achieve propulsion.

关键词： Inertial Propulsion Centrifugal Force Net Impulse Rotating Figure-Eight Mechanism

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Rendezvous and docking sensor and effector system design considerations for the lunar lander Altair

Rendezvous and docking sensor and effector system design con...

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AIAA Guidance, Navigation, and control Conference

作者： Sullivan, Jacob J. Lee, Allan Y. Grover, Myron R. GN and C Autonomous Flight Systems Branch Johnson Space Center Mail Code EG6 2101 NASA Parkway Houston TX 77058 United States Guidance Navigation and Control Section Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive Pasadena CA 91109-8099 United States Guidance Navigation and Control System Altair Lunar Lander Mail Stop 230-104 United States Altair Lunar Lander Systems Engineering Section Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109-8099 United States

ISBN: (纸本)9781600869624

One key function performed by the Guidance, Navigation, and control (GN&C) system of the lunar lander Altair is to rendezvous and dock with the Crew Exploration Vehicle named Orion, in both low Earth orbit and low lunar orbit. The rendezvous and docking process consists of a series of orbital maneuvers and spacecraft attitude controls that successively bring the active vehicle into the vicinity of, and eventually into contact with, the passive vehicle. This paper provides an overview of the rendezvous and docking performance of the Altair GN&C system. To this end, key rendezvous and docking requirements will first be described. These requirements drive the selections of the Altair GN&C sensors, attitude control effectors, and the rendezvous trajectory design. Measurements needed for the rendezvous and docking task will come from the star tracker, inertial measurement unit, docking camera, LIDAR, two-way S-band radiometric ranging data, as well as crew inputs. Measurements from these sensors will be used by the onboard control systems to control well-selected and well-placed Reaction control System (RCS) thrusters to achieve a safe docking. The final contact must be made with the docking axes of the mating vehicles well aligned, both translationally and angularly. Before a high-fidelity simulation test bed is made available, error budgeting is a cost-effective way to assess the docking capability of the Altair and Orion GN&C systems. In docking error budgeting, we first identified all key docking error sources (e.g., attitude control deadbands of mating vehicles, docking sensor measurement error, misalignment between docking sensor and docking mechanism, and others). Results of an error budget study provides the system engineers with a good estimate of whether the GN&C system can achieve the constraints imposed by the docking system. If the docking requirements cannot be met, the relevant error budgets will reveal the source(s) of the problem. Before a high-fidelity

关键词： Budget control

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A Robust Stabilization using State Feedback with Feedforward

A Robust Stabilization using State Feedback with Feedforward

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American control Conference

作者： Kumeresan A. Danapalasingam Anders la Cour-Harbo Girish Chowdhary Morten Bisgaard Section for Automation & Control Department of Electronic Systems Aalborg University 9220 Aalborg Denmark Daniel Guggenheim School of Aerospace Engineering Georgia Institute of Technology Atlanta GA

ISBN: (纸本)9781424474264

关键词： State feedback FEEDFORWARD Liapunov function Error measure external input FEEDFORWARD control There exists control strategy Stabilising

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Computer vision based wheel sinkage detection for robotic lunar exploration tasks

Computer vision based wheel sinkage detection for robotic lu...

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International Conference on Mechatronics and Automation

作者： Hegde, GuruPrasad Robinson, Christopher J. Ye, Cang Stroupe, Ashley Tunstel, Edward Department of Applied Science University of Arkansas at Little Rock Little Rock AR 72204 United States Department of Systems Engineering University of Arkansas at Little Rock Little Rock AR 72204 United States Advanced Robotic Control Group Mobility and Robotic Systems Section Jet Propulsion Laboratory Pasadena CA 91109 United States Johns Hopkins University Applied Physics Laboratory Laurel MD 20723 United States

ISBN: (纸本)9781424451418

This paper presents a wheel sinkage detection method that may be used in robotic lunar exploration tasks. The method extracts the boundary line between a robot wheel and lunar soil by segmenting the wheel-soil images captured from a video camera that monitors wheel-soil interaction. The detected boundary is projected onto the soil-free image of the robot wheel to determine the depth of wheel sinkage. The segmentation method is based on graph theory. It first clusters a wheel-soil image into homogeneous regions called superpixels and constructs a graph on the superpixels. It then partitions the graph into segments by using normalized cuts. Compared with the existing methods, the proposed algorithm is more robust to illumination condition, shadows and dust (covering the wheel). The method's efficacy has been validated by experiments under various conditions. © 2010 IEEE.

关键词： Graph theory

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An experimental and theoretical approach for the biogas steam reforming reaction

An experimental and theoretical approach for the biogas stea...

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作者： Avraam, D.G. Halkides, T.I. Liguras, D.K. Bereketidou, O.A. Goula, M.A. Prefecture Authority of Imathia Section of Town-Planning and Environment GR-59100 Veria Greece Technological Educational Institute of Western Macedonia Pollution Control Technologies Department GR-50100 Koila Kozani Greece HELBIO S.A. Hydrogen and Energy Production Systems Patras Science Park Stadiou Street Platani GR-26504 Rio Greece University of Western Macedonia Department of Mechanical Engineering Bakola and Sialvera GR-50100 Kozani Greece

An experimental and theoretical study for the biogas steam reforming reaction over 5%Ru/Al2O3 catalyst have been performed. An apparatus was constructed for the conduction of the experiments, the core of which was a tube reactor, filled with the catalyst in form of pellets. The inlet gas mixture consisted of CH4 and CO2 in various composition ratios as a model biogas and steam. A theoretical model of the process was developed. The experimental reactor was modelled as an isothermal pseudo homogeneous fixed bed reactor. Internal and external transport phenomena were neglected and appropriate effectiveness factors were employed instead. A physical properties model was used for the calculation of the physicochemical properties of the real mixture. Five reactant species, CH4, CO 2, H2O, CO and H2, were included in the model, whereas the feed consisted of the first three. Steam reforming and water gas shift were the main reactions. Experimental results and theoretical predictions match closely, stability of the catalyst was assured and an optimal operational window was identified, at GHSV = 10,000-20,000 h-1, T = 700-800 °C, CH4/CO2 = 1.0-1.5 and H2O/CH 4 = 3.0-5.0. © 2010 Published by Elsevier Ltd on behalf of Professor T. Nejat Veziroglu.

关键词： Catalysis

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On the estimation of robustness and filtering ability of dynamic biochemical networks under process delays, internal parametric perturbations and external disturbances

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Mathematical Biosciences 2009年第2期222卷 92-108页

作者： Chen, Bor-Sen Chen, Po-Wei Lab. of Control and Systems Biology Department of Electrical Engineering National Tsing-Hua University 101 Section 2 Kuang Fu Road Hsin-chu 300 Taiwan

Inherently, biochemical regulatory networks suffer from process delays, internal parametrical perturbations as well as external disturbances. Robustness is the property to maintain the functions of intracellular biochemical regulatory networks despite these perturbations. In this study, system and signal processing theories are employed for measurement of robust stability and filtering ability of linear and nonlinear time-delay biochemical regulatory networks. First, based on Lyapunov stability theory, the robust stability of biochemical network is measured for the tolerance of additional process delays and additive internal parameter fluctuations. Then the filtering ability of attenuating additive external disturbances is estimated for time-delay biochemical regulatory networks. In order to overcome the difficulty of solving the Hamilton Jacobi inequality (HJI), the global linearization technique is employed to simplify the measurement procedure by a simple linear matrix inequality (LMI) method. Finally, an example is given in silico to illustrate how to measure the robust stability and filtering ability of a nonlinear time-delay perturbative biochemical network. This robust stability and filtering ability measurement for biochemical network has potential application to synthetic biology, gene therapy and drug design. © 2009 Elsevier Inc. All rights reserved.

关键词： Linear matrix inequalities

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Automated diagnostic approaches for defective rolling element bearings using minimal training pattern classification methods

Automated diagnostic approaches for defective rolling elemen...

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4th World Congress on engineering Asset Management: engineering Asset Lifecycle Management, WCEAM 2009

作者： Gryllias, K.C. Yiakopoulos, C. Antoniadis, I. School of Mechanical Engineering Machine Design and Control Systems Section Dynamics and Structures Laboratory Athens 15773 Greece

ISBN: (纸本)9781849960021

Rolling Element Bearings consist one of the most widely used industrial machine elements, being the interface between the stationary and the rotating part of the machine. Due to their importance a plethora of monitoring methods and fault diagnosis procedures have been developed, in order to reduce maintenance costs, improve productivity, and prevent malfunctions and failures during operation which could lead to the downtime of the machine. Towards this direction, among different automatic diagnostic methods, the Support Vector Machine (SVM) method has been shown to present a number of advantages. Support Vector Machine is a relatively new computational learning method based on Statistical Learning Theory and combines fundamental concepts and principles related to learning, well-defined formulation and self-consistent mathematical theory. The key aspects about the use of SVMs as a rolling element bearing health monitoring tool are the lack of actual experimental data, the optimal selection of the type and the number of input features, and the correct selection of the kernel function and its corresponding parameters. A large number of input features have been proposed, being divided in two big categories: A) Traditional signal statistical features in the time domain, such as mean value, rms value, variance, skewness, kurtosis etc, B) Frequency domain based indices, such as energy values obtained at characteristic frequency bands of the measured and the demodulated signals. In this paper, the structure and the performance of a Support Vector Machine based approach for rolling element bearing fault diagnosis is presented. The main advantage of this method is that the training of the SVM is based on a model describing the dynamic behavior of a defective rolling element bearing, enabling thus the direct application of the SVM to experimental measurements of defective bearings, without the need of training the SVM with experimental data of a defective bearing.

关键词： Support vector machines

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